| kljesta64 said: why dont they do 40fps ? |
because TVs work at 60Hz input (even the 100/120/240/480/600/whatever Hz sets, they all really work at 60Hz), so you need to use 30/60 frames in order to have smooth playback
30fps at 60Hz is displayed like this: frame 1, frame 1, frame 2, frame 2, frame 3, frame 3 - every frame is displayed 2 times and that is smooth
60fps ofcourse is just frame 1,frame 2,frame 3 and so on
40fps is displayed likes this: frame 1, frame 1, frame 2, frame 3, frame 3, frame 4, frame 5 - that some frames are just displayed once, while others are displayed twice creates visible stuttering
in the future hopefully even TVs will have adaptable refresh rates (some new PC monitors have that with adaptive synch/free synch/g synch), which makes it possible to lock your game framerates other than pretty much 30 and 60 (15 is unuseable and 120 makes little sense in 60Hz) and still have smooth playback
